Bupap (butalbital / acetaminophen) contains acetaminophen (Tylenol). Taking too much acetaminophen can cause permanent and life-threatening liver damage. Using more than 4000 mg of acetaminophen can cause serious harm to your liver, so be sure not to take more than the recommended dose of Bupap (butalbital / acetaminophen) or other medications that contain acetaminophen.

This is a black box warning. The FDA requires this warning when there is a significant risk of serious or life-threatening effects that anyone taking the drug should consider.

Means that some groups have a high risk of experiencing this side effect